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Mysterious knocking, crunching sound

2000 Honda Accord LX. On the highway, the car purrs. But going slowly over uneven neighborhood roads, I hear a muffled “knocking” sound coming from under the hood near the tires on the drivers side and generally across the front bottom of the car near the wheels. It’s not consistent. Mechanics changed tires, did a wheel alignemen and hoped it would go away, but it did not. They did a visual inspection and tightened everything under the car, but they can’t find anything wrong. Meantime it seems to be getting louder. Struts? Suspension? what should I check next to avoid this from becoming worse (and more expensive)?

I forgot to add the car has 137,000 miles on it. All scheduled maintenance has been performed by dealer.

[b][i]Two Ideas:

Idea 1
Honda Dealers Have A Tool Called The "Steelman ChassisEAR™ Diagnostic Tool.[/i][/b]

The tool consists of 6 clip-on microphones and headphones and is supposed to be useful to technicians for locating body rattles, creaks, and squeaks. The technician can select different microphones to listen to during a test drive. There are Service Bulletins that tell how to set-up for different noise complaints.

Idea 2
Please note that a 2000 model-year vehicle will very soon be eleven model-years old. That’s 77 years-old in “car years”. Just like people, as cars transition into senior citizens they develop assorted mysterious aches, pains, and weird sounds, some of which can never be explained or the cost of doing so is so high it isn’t worth it.

Be sure the car is safe to drive and turn the radio up a bit.

CSA

Thanks for reply, that is helpful. Interestingly, the service manual for this car only shows a maintenance schedule for up to 122,000 miles. This car is still going strong (and I hope it will for a while longer). Mechanics say it’s safe to drive … and the radio works fine.

You’re Welcome.

Are the mechanics that did the “inspection and tightened everything” actual Honda car mechanics, working mainly on Hondas ? The reason I ask is that many (most) car models develop sounds, many of which are specific to a certain make, model, model-year range, etcetera.

Sometimes certain vehicles have links, mounts, or bushings, etcetera, that go bad at about a predicted age or number of miles and those spots are suspect right away.

General mechanics could have a harder time locating a certain sound that is familiar to Honda specific, Honda experienced mechanics. I’d even call around to places that have specialized in Hondas for a while and describe your situation and see if any think it would be a relatively simple diagnosis.

CSA

Yea, Honda mechanics at the dealer. They couldn’t find anything. If links, mounts or bushings “go bad”, it that dangerous or just annoying? The mechanic rode with me on the highway on two different occasions to try to find (and hear) the noise, but of course it doesn’t occur on the highway, so they never heard it.